U.S. patent application number 16/644136 was filed with the patent office on 2020-06-18 for switch device.
The applicant listed for this patent is KABUSHIKI KAISHA TOKAI RIKA DENKI SEISAKUSHO. Invention is credited to Tetsuya EGAWA, Tatsushi KATSUYAMA, Takeyoshi MORI, Takashi NAGAO.
Application Number | 20200189641 16/644136 |
Document ID | / |
Family ID | 65811104 |
Filed Date | 2020-06-18 |
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United States Patent
Application |
20200189641 |
Kind Code |
A1 |
KATSUYAMA; Tatsushi ; et
al. |
June 18, 2020 |
SWITCH DEVICE
Abstract
A switch device that is installed on a steering wheel of a
vehicle. The switch device includes a switch part that is installed
on the vehicle and includes an operation knob and an
electromagnetic element for detecting an operation on the operation
knob and causing a vibration of the operation knob, and a control
unit that performs at least one of a first control and a second
control, the first control controlling the electromagnetic element
such that the operation knob vibrates in response to the operation,
and the second control controlling the electromagnetic element such
that the operation knob vibrates at an audible band. The switch
device is positioned such that a directivity of a sound emitted
from the operation knob is increased toward an ear of an occupant
of the vehicle.
Inventors: |
KATSUYAMA; Tatsushi; (Aichi,
JP) ; NAGAO; Takashi; (Aichi, JP) ; EGAWA;
Tetsuya; (Aichi, JP) ; MORI; Takeyoshi;
(Aichi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOKAI RIKA DENKI SEISAKUSHO |
Aichi |
|
JP |
|
|
Family ID: |
65811104 |
Appl. No.: |
16/644136 |
Filed: |
August 28, 2018 |
PCT Filed: |
August 28, 2018 |
PCT NO: |
PCT/JP2018/031793 |
371 Date: |
March 3, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04R 3/12 20130101; H04R
17/00 20130101; B62D 1/06 20130101; B60R 11/02 20130101; G05G 1/02
20130101; B60R 16/02 20130101; G05G 5/03 20130101; H01H 9/16
20130101; H04S 2400/11 20130101; H04S 1/00 20130101; H04R 2499/13
20130101; B60K 35/00 20130101; B62D 1/046 20130101; H04S 7/00
20130101; H04S 1/007 20130101; H01H 13/02 20130101 |
International
Class: |
B62D 1/06 20060101
B62D001/06; B60R 11/02 20060101 B60R011/02; H01H 9/16 20060101
H01H009/16; B60R 16/02 20060101 B60R016/02; G05G 1/02 20060101
G05G001/02; G05G 5/03 20060101 G05G005/03; H01H 13/02 20060101
H01H013/02; H04S 1/00 20060101 H04S001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 19, 2017 |
JP |
2017-179096 |
Claims
1. A switch device that is installed on a steering wheel of a
vehicle, the switch device comprising: a switch part that is
installed on the vehicle and comprises an operation knob and an
electromagnetic element for detecting an operation on the operation
knob and causing a vibration of the operation knob; and a control
unit that performs at least one of a first control and a second
control, the first control controlling the electromagnetic element
such that the operation knob vibrates in response to the operation,
and the second control controlling the electromagnetic element such
that the operation knob vibrates at an audible band, wherein the
switch device is positioned such that a directivity of a sound
emitted from the operation knob is increased toward an ear of an
occupant of the vehicle.
2. The switch device according to claim 1, wherein as the second
control, the control unit drives the electromagnetic element so
that a warning tone or warning sound is output from the operation
knob.
3. The switch device according to claim 2, wherein the control unit
outputs a sine-wave drive signal with a frequency in the audible
band to the electromagnetic element so that the warning tone is
output from the operation knob.
4. The switch device according to claim 2, wherein the control unit
outputs a drive signal based on a sound signal in the audible band,
to the electromagnetic element so that the warning sound is output
from the operation knob.
5. The switch device according to claim 1, wherein the
electromagnetic element comprises a piezoelectric element.
6. The switch device according to claim 1, wherein the number of
the switch parts provided on the steering wheel is at least two,
and wherein the control unit performs, as a part of the second
control, control of properties of sound output from each switch
part so that a three-dimensional audio image produced by sounds
output from the switch parts is maintained.
7. The switch device according to claim 6, wherein the at least two
switch parts are arranged across a center line passing through the
center of a seat or the steering wheel in the vehicle.
8. The switch device according to claim 6, wherein one of the at
least two switch parts which is located on a right side with
respect to the center line is positioned to increase the
directivity toward a right ear of the occupant, and wherein one of
the at least two switch parts which is located on a left side with
respect to the center line is positioned to increase the
directivity toward a left ear of the occupant.
9. The switch device according to claim 6, wherein the control unit
comprises a phase shift means and an adding means, wherein the
phase shift means performs a phase-delay process to the sound
signal of a right channel corresponding to the one of the at least
two switch parts located on the right side with respect to the
center line and to the sound signal of a left channel corresponding
to the one of the at least two switch parts located on the left
side with respect to the center line, and wherein the adding means
outputs a drive signal of the right and left channels respectively
by adding the sound signal of the right channel to the sound signal
of the left channel phase-delayed by the phase shift means and the
sound signal of the left channel to the sound signal of the right
channel phase-delayed by the phase shift means.
10. The switch device according to claim 9, wherein the control
unit sets respective phase differences in the phase shift means so
that, at the right ear of the occupant, a synthetic sound of sound
based on the sound signal of the right channel and sound based on
the sound signal of the right channel phase-delayed by the phase
shift means is maximized and a synthetic sound of sound based on
the sound signal of the left channel and sound based on the sound
signal of the left channel phase-delayed by the phase shift means
is minimized, and at the left ear of the occupant, a synthetic
sound of sound based on the sound signal of the left channel and
sound based on the sound signal of the left channel phase-delayed
by the phase shift means is maximized and a synthetic sound of
sound based on the sound signal of the right channel and sound
based on the sound signal of the right channel phase-delayed by the
phase shift means is minimized.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] The present application claims the priority of Japanese
patent application No. 2017/179096 filed on Sep. 19, 2017, and the
entire contents of Japanese patent application No. 2017/179096 are
hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a switch device.
BACKGROUND ART
[0003] An acoustic system is present which is mounted on a vehicle
to inform the situation of the surroundings of the vehicle by a
three-dimensional audio image. The acoustic system is provided with
a speaker for emitting sound, and a control unit from which an
output signal corresponding to the situation of the surroundings of
the vehicle is output to the speaker (see, e.g., Patent Literature
1). The control unit has a means for deriving parameters associated
with driving safety such as positions and relative speeds of plural
running vehicles around own vehicle and inter-vehicle distances, a
means for determining the imminent danger level for own vehicle by
comparing the parameters to conditions which are preset for
determining the imminent danger level, a signal conversion circuit
means for converting a signal of the parameter into a virtual sound
source generation signal according to the result of determining the
imminent danger level, a means for converting the virtual sound
source generation signal into a pulse-like amplified signal by
using a signal amplifier circuit, and a signal processing circuit
means which inputs the amplified signal to the speaker to produce
pulse sound at a position of the virtual sound source.
CITATION LIST
Patent Literature
[0004] Patent Literature 1: JP 2002/133596 A
SUMMARY OF INVENTION
Technical Problem
[0005] The acoustic system disclosed in Patent Literature 1 causes
a problem that it needs to be separately provided with the speaker
to emit a sound in order to generate three-dimensional audio images
inside the vehicle interior.
[0006] It is an object of the invention to provide a switch device
which is installed on a steering wheel to generate the
three-dimensional audio images.
Solution to Problem
[0007] According to an embodiment of the invention, a switch device
may be configured as defined by [1] to [10] below.
[0008] [1] To achieve the above-mentioned object, provided is a
switch device that is installed on a steering wheel of a vehicle,
the switch device comprising: a switch part that is installed on
the vehicle and comprises an operation knob and an electromagnetic
element for detecting an operation on the operation knob and
causing a vibration of the operation knob; and a control unit that
performs at least one of a first control and a second control, the
first control controlling the electromagnetic element such that the
operation knob vibrates in response to the operation, and the
second control controlling the electromagnetic element such that
the operation knob vibrates at an audible band, wherein the switch
device is positioned such that a directivity of a sound emitted
from the operation knob is increased toward an ear of an occupant
of the vehicle.
[0009] [2] The switch device according to [1], wherein as the
second control, the control unit drives the electromagnetic element
so that a warning tone or warning sound is output from the
operation knob.
[0010] [3] The switch device according to [2], wherein the control
unit outputs a sine-wave drive signal with a frequency in the
audible band to the electromagnetic element so that the warning
tone is output from the operation knob.
[0011] [4] The switch device according to [2], wherein the control
unit outputs a drive signal based on a sound signal in the audible
band, to the electromagnetic element so that the warning sound is
output from the operation knob.
[0012] [5] The switch device according to any one of [1] to [4],
wherein the electromagnetic element comprises a piezoelectric
element.
[0013] [6] The switch device according to any one of [1] to [5],
wherein the number of the switch parts provided on the steering
wheel is at least two, and wherein the control unit performs, as a
part of the second control, control of properties of sound output
from each switch part so that a three-dimensional audio image
produced by sounds output from the switch parts is maintained.
[0014] [7] The switch device according to [6], wherein the at least
two switch parts are arranged across a center line passing through
the center of a seat or the steering wheel in the vehicle.
[0015] [8] The switch device according to [6] or [7], wherein one
of the at least two switch parts which is located on a right side
with respect to the center line is positioned to increase the
directivity toward a right ear of the occupant, and wherein one of
the at least two switch parts which is located on a left side with
respect to the center line is positioned to increase the
directivity toward a left ear of the occupant.
[0016] [9] The switch device according to any one of [6] to [8],
wherein the control unit comprises phase shift means and adding
means, wherein the phase shift means performs a phase-delay process
to the sound signal of a right channel corresponding to the one of
the at least two switch parts located on the right side with
respect to the center line and to the sound signal of a left
channel corresponding to the one of the least two switch parts
located on the left side with respect to the center line, and
wherein the adding means outputs a drive signal of the right and
left channels respectively by adding the sound signal of the right
channel to the sound signal of the left channel phase-delayed by
the phase shift means and the sound signal of the left channel to
the sound signal of the right channel phase-delayed by the phase
shift means.
[0017] [10] The switch device according to [9], wherein the control
unit sets respective phase differences in the phase shift means so
that, at the right ear of the occupant, a synthetic sound of sound
based on the sound signal of the right channel and sound based on
the sound signal of the right channel phase-delayed by the phase
shift means is maximized and a synthetic sound of sound based on
the sound signal of the left channel and sound based on the sound
signal of the left channel phase-delayed by the phase shift means
is minimized, and at the left ear of the occupant, a synthetic
sound of sound based on the sound signal of the left channel and
sound based on the sound signal of the left channel phase-delayed
by the phase shift means is maximized and a synthetic sound of
sound based on the sound signal of the right channel and sound
based on the sound signal of the right channel phase-delayed by the
phase shift means is minimized.
Advantageous Effects of invention
[0018] According to an embodiment of the invention, it is possible
to provide a switch device which is installed on a steering wheel
to generate the three-dimensional audio images.
BRIEF DESCRIPTION OF DRAWINGS
[0019] FIG. 1 is a front view showing a switch device in an
embodiment in the case of being mounted on a steering wheel of a
vehicle when viewing the steering wheel from a driver.
[0020] FIG. 2 is a cross sectional view showing the switch device
taken along a line A-A in FIG. 1.
[0021] FIG. 3 is a top view showing an arrangement example of the
switch device when viewing the vehicle from above, in the case that
the switch device in the embodiment is mounted on the steering
wheel of the vehicle.
[0022] FIG. 4 is a side view when the switch device is viewed in
the direction C in FIG. 3.
[0023] FIG. 5 is a schematic block diagram illustrating a
configuration of the switch device in the embodiment.
[0024] FIG. 6 shows an waveform example of a drive signal of a
right channel for driving an operation knob, wherein a drive signal
Sh1 is to provide tactile sensation by causing vibration of the
operation knob in response to a touch operation, a drive signal Ss1
is to produce a beep from the operation knob, and a drive signal
Ss1' is to produce a sound from the operation knob.
DESCRIPTION OF EMBODIMENTS
Embodiment of the Invention
[0025] The switch device in the embodiment of the invention is a
switch device 1 which is arranged in a steering wheel 8 of a
vehicle 5 and has switch parts 30, 40 that are installed in the
vehicle 5 and are provided with operation knobs 31, 41 and piezo
elements 32, 42 acting as electromagnetic elements that detect an
operation on the operation knobs 31, 41 and also cause vibration of
the operation knobs 31, 41, and a control unit 100 that performs at
least one of first control and second control, the first control
being performed to control the piezo elements 32, 42 such that the
operation knobs 31, 41 vibrate in response to the operation, and
the second control being performed to control the piezo elements
32, 42 such that the operation knobs 31, 41 vibrate in the audible
band, and the switch device 1 is positioned to achieve high
directivity such that sounds emitted from the operation knobs 31,
41 are concentrated toward the ears of a driver 20 that is an
occupant of the vehicle 5.
[0026] In the present embodiment, an example in which the occupant
is the driver 20 will be described.
[0027] (Switch Parts 30 and 40)
[0028] As shown in FIG. 1, the switch parts 30, 40 are attached to
the steering wheel 8 of the vehicle 5. One or two or more switch
parts are provided on the steering wheel 8. In the present
embodiment, an example in which the two switch parts 30, 40 are
symmetrically arranged across a center line 8a of the steering
wheel 8 as shown in FIG. 1 will be described.
[0029] The switch parts 30, 40 are switches associated with vehicle
operation and are steering switches which can be used for
air-conditioning control, audio control, and car navigation
operation, etc. The switch parts 30, 40 can be electrically
connected to a vehicle main body via, e.g., a steering roll
connector (not shown). A right sound signal S1 and a left sound
signal S2, etc., to the switch parts 30, 40 can be input from the
vehicle main body via, e.g., the steering roll connector.
[0030] As shown in FIG. 2, the switch part 30 is generally composed
of the operation knob 31 which is a plate-shaped panel, and the
piezo element 32 which is an electromagnetic element connected to
the operation knob 31 via a transmission member 35. The
transmission member 35 is a columnar body formed of a material
capable of easily transmitting a force or vibration, e.g., a metal,
a resin or an elastic body such as rubber. The piezo element 32 is
mounted on a substrate 33 which is provided on a spoke 9. As shown
in FIG. 2, the operation knob 31 is a plate-shaped panel and is
arranged to be flush with the surface of the spoke 9, hence, a
seamless switch with no level difference. The switch part 40 has
the same configuration.
[0031] The piezo element 32 is, e.g., a unimorph piezoelectric
element provided with a piezoelectric body having a disc shape and
a metal shim having a disc shape with a larger radius than the
piezoelectric body. An upper wiring is electrically connected to
the piezoelectric body of the piezoelectric element and a lower
wiring is electrically connected to the metal shim of the
piezoelectric element.
[0032] As a modification, the piezoelectric element may be, e.g., a
bimorph piezoelectric element in which two piezoelectric bodies are
provided on both sides of the metal shim.
[0033] The material used to form the piezoelectric body is, e.g.,
lithium niobate, barium titanate, lead titanate, lead zirconate
titanate (PZT), lead metaniobate or polyvinylidene fluoride (PVDF),
etc. The piezoelectric body is, e.g., a stacked piezoelectric body
formed by stacking films of these materials. The piezoelectric body
is poled in a thickness direction and produces larger output when
deformed in the thickness direction. The metal shim is formed of,
e.g., conductive phosphor bronze or conductive stainless steel,
etc.
[0034] When the operation knob 31 is pushed, the piezo element 32
generates voltage corresponding to the pushing force and produces a
push operation signal S0. The piezo element 32 thereby acts as a
switching element which detects an operation on the operation knob
31.
[0035] The piezo element 32 also deforms upon application of
voltage and displaces the operation knob 31, which is connected
thereto via the transmission member 35, in a vertical direction B
shown in FIG. 2. The piezo element 32 thereby acts as an actuator
which provides tactile sensation from the piezo element 32 side to
the finger, etc., performing an operation on the operation knob 31
and also acts as a sound source which produces sound by vibration
of the operation knob 31 in the audible band caused by the piezo
element 32.
[0036] By having the configuration described above, the operation
knob 31 acts as a touch portion for providing tactile sensation and
also acts as a sound source (speaker) for producing sound by being
vibrated in the audible band. Therefore, the switch parts 30, 40
can output sound in a predetermined frequency band and can output,
e.g., warning tones or warning sound, etc., based on control from
the vehicle side.
[0037] The electromagnetic element is not limited to the piezo
element 32 described above. It is possible to use, e.g., a voice
coil motor which is composed of a magnetic circuit and a coil and
is configured to detect an operation force on the coil based on a
current produced in the coil by the movement thereof and to
generate vibration by movement of the coil caused by a change in
the magnetic field on the magnetic circuit side.
[0038] In FIG. 3, a direction from the switch part to the ears of
the driver 20 and from the front toward the rear of the vehicle 5
is defined as the X direction, a width direction of the vehicle 5
is defined as the Y direction, and a vertical direction of the
vehicle 5 as the cross product of the X axis and the Y axis is
defined as the Z direction. As shown in FIG. 3, the switch part 30
is positioned to have high directivity in a direction toward the
right ear 21 of the driver 20. Likewise, the switch part 40 is
positioned to have high directivity in a direction toward the left
ear 22 of the driver 20. That is, by mounting the switch parts 30,
40 on the steering wheel 8, an output axis 30a of the switch part
30 can be oriented in the direction toward the right ear 21 of the
driver 20, and an output axis 40a of the switch part 40 can be
oriented in the direction toward the left ear 22 of the driver
20.
[0039] Meanwhile, as shown in FIG. 4, the switch part 40 is
arranged to face slightly upward and toward the ears of the driver
20. Thus, the X axis and the Z axis are slightly rotated about the
Y axis, as shown in FIG. 4.
[0040] As shown in FIG. 4, since the switch parts 30, 40 are
mounted on the steering wheel 8, the switch part 40 is arranged to
face slightly upward (the X axis direction) so that the output axis
40a of the switch part 40 is oriented in the direction toward the
left ear 22 of the driver 20. The switch part 30 is also arranged
to face slightly upward (the X axis direction) in the same manner.
In this arrangement, the two switch parts 30, 40 has high
directivity in the direction toward the ears 21, 22 of the
occupant. Thus, sounds emitted from the operation knobs 31, 41 are
concentrated toward the ears 21, 22 of the driver 20 of the vehicle
5.
[0041] (Configuration of the Control Unit 100)
[0042] The control unit 100 is provided with, e.g., a microcomputer
composed of a CPU (Central Processing Unit) performing
predetermined calculation and processing, etc., according to a
stored program, a RAM (Random Access Memory) and a ROM (Read Only
Memory) as semiconductor memories, etc. The ROM stores, e.g., a
program for operation of the control unit 100 and various
parameters, etc. The control unit 100 is also provided with a sound
image controller 101 to control sound image localization.
[0043] As shown in FIG. 5, the switch parts 30, 40 are connected to
the control unit 100. Push operation signals S.sub.O1 and S.sub.O2
are input from the switch parts 30, 40. Then, in response to the
push operation signals S.sub.O1 and S.sub.O2, tactile sensation
presentation signals Sh1, Sh2 to provide tactile sensation are
output to the piezo elements 32, 42 of the switch parts 30, 40. In
addition, sound signals Ss1, Ss2 to output warning tones or warning
sound, etc., are also output to the piezo elements 32, 42 of the
switch parts 30, 40 via the sound image controller 101.
[0044] (Tactile Sensation Presentation Control by the Control Unit
100)
[0045] As the first control, the control unit 100 controls the
piezo elements 32, 42 so that the operation knobs 31, 41 vibrate in
response to the operation. That is, based on the push operation
signals S.sub.O1 and S.sub.O2, tactile sensation can be provided by
vibration, etc., to an operator operating the operation knobs 31,
41. When a push operation is performed, the control unit 100
outputs the tactile sensation presentation signals Sh1, Sh2 to the
piezo elements 32, 42 to, e.g., thrust the operation knobs 31, 41
upward once or several times with a predetermined force, thereby
providing tactile sensation. Alternatively, tactile sensation can
be provided by vibrating at a predetermined cycle.
[0046] (Sound Image Localization Control by the Control Unit
100)
[0047] As the second control, the control unit 100 controls the
piezo elements 32, 42 so that the operation knobs 31, 41 vibrate in
the audible band. In addition, as a part of the second control, the
control unit 100 controls properties of sound output from each of
the switch parts 30, 40 so that a three-dimensional audio image
produced by sounds output from the switch parts 30, 40 is
maintained. This control is performed as follows.
[0048] As shown in FIG. 3, a drive part 110 for driving the switch
part 30 (the piezo element 32) and a drive part 120 for driving the
switch part 40 (the piezo element 42) are provided in the sound
image controller 101. The drive part 110 drives the switch part 30
by amplifying the right sound drive signal Ss1 obtained by adding
the right sound signal S1 to a phase shifted signal S21 of the left
sound signal S2. Likewise, the drive part 120 drives the switch
part 40 by amplifying the left sound drive signal Ss2 obtained by
adding the left sound signal S2 to a phase shifted signal S12 of
the right sound signal S1. Thus, the operation knob 31 of the
switch part 30 vibrates, resulting in output of sound of the right
channel based on the right sound drive signal Ss1, and also the
operation knob 31 of the switch part 40 vibrates, resulting in
output of sound of the left channel based on the left sound drive
signal Ss2.
[0049] A phase shift circuit 115 shifts (delays) the phase of the
right sound signal S1 and then outputs the phase shifted signal S12
to the drive part 120. For the phase shift, a phase difference
.alpha. between the right sound signal S1 and the phase shifted
signal S12 can be appropriately set.
[0050] Likewise, a phase shift circuit 125 shifts (delays) the
phase of the left sound signal S2 and then outputs the phase
shifted signal S21 to the drive part 110. For the phase shift, a
phase difference .alpha. between the left sound signal S2 and the
phase shifted signal S21 can be appropriately set. In this regard,
the phase difference .alpha. here is used when the switch parts 30,
40 are symmetrically arranged across a center line 11 of a seat 10,
and the phase difference can be different between the phase shift
circuit 115 and the phase shift circuit 125 when, e.g., the switch
parts 30, 40 are asymmetrically arranged across the center line 11
of the seat 10.
[0051] Gains of the drive parts 110, 120 and the phase shift
circuits 115, 125 can be adjusted respectively. Thus, as shown in
FIG. 3, it is possible to adjust an addition ratio of the right
sound signal S1 to the phase shifted signal S21 in the drive part
110 and an addition ratio of the left sound signal S2 to the phase
shifted signal S12 in the drive part 120. In addition, it is
possible to adjust sound pressure output from the operation knob 31
of the switch part 30 and from the operation knob 41 of the switch
part 40 and it is also possible to adjust the balance of stereo
sound between left and right.
[0052] The control unit 100 controls properties of sound output
from each switch part so that a three-dimensional audio image
produced by sounds output from the two operation knobs 31, 41 is
maintained.
[0053] Sound SD1 of the right channel and phase-shifted sound SD2d
of the left channel, which are output from the switch part 30, and
sound SD2 of the left channel and phase-shifted sound SD1d of the
right channel, which are output from the switch part 40, reach the
right ear 21.
[0054] The sound of the right channel reaching the right ear 21 is
the sound SD1 of the right channel and the phase-shifted sound SD1d
of the right channel.
[0055] The sound of the left channel reaching the right ear 21 is
the sound SD2 of the left channel and the phase-shifted sound SD2d
of the left channel.
[0056] Based on this, the control unit 100 performs control so that
a synthetic sound of the sound SD1 of the right channel and the
phase-shifted sound SD1d of the right channel is maximized and a
synthetic sound of the sound SD2 of the left channel and the
phase-shifted sound SD2d of the left channel is minimized.
[0057] In order that the synthetic sound of the sound SD1 of the
right channel and the phase-shifted sound SD1d of the right channel
is maximized at the right ear 21, for example, the control unit 100
sets the phase difference .alpha. so that the phase difference
between the sound SD1 travelling a distance L11 and the sound SD1d
travelling a distance L21 is 2.pi.n (n=0, 1, 2 . . . ). Here, the
distance L11 is a distance from the switch part 30 to the right ear
21, and the distance L21 is a distance from the switch part 40 to
the right ear 21.
[0058] In order that the synthetic sound of the sound SD2 of the
left channel and the phase-shifted sound SD2d of the left channel
is minimized at the right ear 21, the phase difference .alpha. is
set so that the phase difference between the sound SD2 travelling
the distance L21 and the sound SD2d travelling the distance L11 is
.pi.n (n=0, 1, 2 . . . ).
[0059] At the position of the right ear 21, the sound SD1 of the
right channel and the sound SD2 of the left channel cancel each
other out or crosstalk therebetween is reduced by the
above-described setting in which the synthetic sound of the sound
SD2 of the left channel and the phase-shifted sound SD2d of the
left channel is minimized at the right ear 21.
[0060] Likewise, the sound SD2 of the left channel and the
phase-shifted sound SD1d of the right channel, which are output
from the switch part 40, and the sound SD1 of the right channel and
the phase-shifted sound SD2d of the left channel, which are output
from the switch part 30, reach the left ear 22.
[0061] The sound of the left channel reaching the left ear 22 is
the sound SD2 of the left channel and the phase-shifted sound SD2d
of the left channel.
[0062] The sound of the right channel aching the left ear 22 is the
sound SD1 of the right channel and the phase-shifted sound SD1d of
the right channel.
[0063] Based on this, the control unit 100 performs control so that
a synthetic sound of the sound SD2 of the left channel and the
phase-shifted sound SD2d of the left channel is maximized and a
synthetic sound of the sound SD1 of the right channel and the
phase-shifted sound SD1d of the right channel is minimized.
[0064] In order that the synthetic sound of the sound SD2 of the
left channel and the phase-shifted sound SD2d of the left channel
is maximized at the left ear 22, for example, the control unit 100
sets the phase difference .alpha. so that the phase difference
between the sound SD2 travelling a distance L22 and the sound SD2d
travelling a distance L12 is 2.pi.n (n=0, 1, 2 . . . ). Here, the
distance L22 is a distance from the switch part 40 to the left ear
22, and the distance L12 is a distance from the switch part 30 to
the left ear 22.
[0065] In order that the synthetic sound of the sound SD1 of the
right channel and the phase-shifted sound SD1d of the right channel
is minimized at the left ear 22, the phase difference a is set so
that the phase difference between the sound SD1 travelling the
distance L12 and the sound SD1d travelling the distance L22 is
.pi.n (n=0, 1, 2 . . . ).
[0066] At the position of the left ear 22, the sound SD2 of the
left channel and the sound SD1 of the right channel cancel each
other out or crosstalk therebetween is reduced by the
above-described setting in which the synthetic sound of the sound
SD1 of the right channel and the phase-shifted sound SD1d of the
right channel is minimized at the left ear 22.
[0067] Due to the phase shift controlled by the control unit 100,
it is possible to allow sound to be localized at the ears and it is
also possible to perform control so that a three-dimensional audio
image produced by sounds output from the two switch parts 30, 40 is
maintained.
[0068] (Operation Example of the Switch Parts 30 and 40)
[0069] The operation of the switch parts 30, 40 will be described
using a waveform example of the drive signal of the right channel
shown in FIG. 6 which is a signal for driving the operation knob.
The control unit 100 outputs, e.g., the drive signal Sh1 for
tactile sensation presentation to the piezo element 32 at time t1
in response to the push operation on the operation knob and thereby
makes the operation knob 31 vibrate. Tactile sensation is presented
by, e.g., motion of thrusting the operation knob 31 upward by a
single pulse, as shown in FIG. 6.
[0070] Then, at time t2, a sine wave with a frequency in the
audible band is generated as the drive signal Ss1' and is output to
the piezo element 32, thereby vibrating the operation knob 31. This
produces a beep as a warning tone which provides a warning
announcement to the driver 20. The switch part 30 acts as a sound
source (speaker) for producing warning sound.
[0071] Then, at time t3, a sound signal in the audible band is
generated as the drive signal Ss1 and is output to the piezo
element 32 via the sound image controller 101. A sound signal in
the audible band, which corresponds to the drive signal Ss1 in a
stereo manner, is also generated as the drive signal Ss2 of the
left channel and is output to the piezo element 42 via the sound
image controller 101. Thus, the operation knobs 31, 41 can vibrate
in response to the sound signals. The switch parts 30, 40 can act
as sound sources (speakers) for generating warning sound and allow
for sound localization control so that a three-dimensional audio
image is maintained.
[0072] The present embodiment is not limited to the use of two
switch parts and is also applicable to when not less than three
switch parts are arranged across the center line 8a of the steering
wheel. That is, taking into consideration the distance from the
switch part to the ear of the occupant and the phase difference for
the sound output from each switch port, the phase difference is set
so that the synthetic sounds are maximized/minimized at the right
ear and the left ear respectively, and this cancels out sounds of
the right and left channel and reduces crosstalk therebetween.
Thus, even in case that three or more switch parts are provided, it
is possible to allow sound to be localized at the ears and it is
also possible to perform control so that a three-dimensional audio
image produced by sounds output from the three or more switch parts
is maintained.
Effects of the Embodiment
[0073] The following effects are obtained in the embodiment of the
invention.
[0074] (1) The switch device in the embodiment of the invention is
the switch device 1 which is arranged in the steering wheel 8 of
the vehicle 5 and has the switch parts 30, 40 that are installed in
the vehicle 5 and are provided with the operation knobs 31, 41 and
the piezo elements 32, 42 acting as electromagnetic elements that
detect an operation on the operation knobs 31, 41 and also cause
vibration of the operation knobs 31, 41, and the control unit 100
that performs at least one of first control and second control, the
first control being performed to control the piezo elements 32, 42
such that the operation knobs 31, 41 vibrate in response to the
operation, and the second control being performed to control the
piezo elements 32, 42 such that the operation knobs 31, 41 vibrate
in the audible band, and the switch device 1 is positioned to
achieve high directivity such that sounds emitted from the
operation knobs 31, 41 are concentrated toward the ears of the
driver 20 that is an occupant of the vehicle 5. As a result, the
switch parts act to provide tactile sensation in response to the
push operation on the operation knobs under the first control, and
also act as sound sources (speakers) for generating sound by being
vibrated in the audible band under the second control.
[0075] (2) The switch part can be mounted on the steering wheel,
etc., of the vehicle main body. Therefore, it is not necessary to
provide a space for mounting a speaker for producing sound and this
contributes to size reduction.
[0076] (3) Since the electromagnetic element (the piezo element)
provided on the switch part to provide tactile sensation can be
also used to produce tone or sound, the switch device 1 can have a
speaker function without increasing the cost.
[0077] Although some embodiments of the invention have been
described above, the embodiments are merely exemplary and the
invention according to claims is not to be limited thereto. These
new embodiments may be implemented in various other forms, and
various omissions, substitutions and changes, etc., can be made
without departing from the gist of the invention. In addition, all
combinations of the features described in these embodiments are not
necessary to solve the problem of the invention. Further, these
embodiments are included within the scope and gist of the invention
and also within the invention described in the claims and the
equivalency thereof.
REFERENCE SIGNS LIST
[0078] 1 SWITCH DEVICE
[0079] 5 VEHICLE
[0080] 8 STEERING WHEEL
[0081] 8a CENTER LINE
[0082] 10 SEAT
[0083] 11 CENTER LINE
[0084] 20 DRIVER
[0085] 21 RIGHT EAR
[0086] 22 LEFT EAR
[0087] 30 SWITCH PART
[0088] 31 OPERATION KNOB
[0089] 32 PIEZO ELEMENT
[0090] 40 SWITCH PART
[0091] 41 OPERATION KNOB
[0092] 42 PIEZO ELEMENT
[0093] 100 CONTROL UNIT
[0094] 110 DRIVE PART
[0095] 115 PHASE SHIFT CIRCUIT
[0096] 120 DRIVE PART
[0097] 125 PHASE SHIFT CIRCUIT
* * * * *